Yes, I have a Creative Cloud subscription. And I have the Creative Suite Design Premium CS4 installed on my computer. This morning i started the installation with antivirus deactivated but the routine stopped again with the error code EX11. Where are the temporary files located? Do the folders need special rights?

Install under a different profile with admin privileges. The one your using is corrupt or the username is to long like noted in my response on the 24th. especially if you have a domain profile. Let us know if that worked.